Hi Maurice,
Apologies for the delay in responding to this. I've taken a look into this and like you could not find any documentation to support this feature. The description you've provided also appears to be spot on in terms of the processes and logic for how this feature could be used.

As you've stated it the posenddate option has been designed for when a user leaves a company and for the use case scenario of a user being promoted then this would require two actions.

Based on you creating this forum post I've now requested that we update our documentation and have copied the information you've provided as it provides a good basis for us to make these changes.
Thanks

Tom WoodTotara Product Support